As various wireless communication technologies for supporting different frequency bands have been provided, technologies for effectively supporting multi-frequency bands have been researched and developed. For example, a wireless communication system has used a method of having a separate transmission and reception module while being classified according to each of frequency bands to support multi-frequency bands.
FIG. 1 illustrates a transmission and reception module of a Base Station (BS) for supporting multi-frequency bands.
As shown in FIG. 1, each of a macro BS 100-1 and a distributed BS 100-2, which supports multi-frequency bands of f1 to f4, includes a separate transmission and reception module for supporting each of the multi-frequency bands of f1 to f4. However, as described above, the method in which the BS includes the number of corresponding transmission and reception modules to support a plurality of frequency bands has a problem in that the more the number of supported frequency bands is increased, the more a hardware size is increased.
Therefore, recently, in order to miniaturize a size of the BS which supports the multi-frequency bands, there has been a method of reducing a separation distance of an antenna array configuring an antenna unit. However, there is a limit to miniaturize the size of the BS using only the method of the separation distance of the antenna array.